Just to layer on with MZ. My IC believes men are often SO SIMPLE. The OW simply makes them feel good about themselves. I've been saying what I think are basic statements to my H like "I wonder what our marriage would be like if you put the same energy into our marriage as your affair?" From the look on his face, I can tell he hadn't ever thought about it.
For me, I had evidence from text messages/internet that my H was obsessively texting another woman. I found out within 6 weeks of it starting. I confronted H and he initally denied a PA. We went to a MC and the MC told him to tell me the truth and answer any of my questions. That night, he admitted to a PA and answered my questions.
Now, my H has then continued the A and wanted to stay married for the last 5 months. I've told him we need to separate now that the holidays are done because I can't live like this anymore. Frankly, for me, it's been worth having it out in the open and while I did the DB-ing approach...I also felt like I needed H to know I knew.
I'm not sure much makes a difference when your H is in an affair. However, if you aren't happy...something has to change. Either change yourself and decide to just put up with what seems like an affair....or, let him know you suspect something, and you don't want to live like this.
From what I've read about affairs, your H could have an affair where he gets a couple needs met by the OW, and other needs met by you. Those types of affairs can continue for a long time unless someone forces the issue. (I've read examples where they last 30 years)
On the other hand, if the OW has any sort of self esteem, she has to be getting tired of this too. However, if it's already gone on this long, she may just be in it for a couple needs to and she may not care about any long-term relationship with your husband.
You sound to me like you are at the point where you know something has to change. I just don't see how talking to your H can make things much worse. Frankly too, I swear my H doesn't remember most of our conversations...so even if you say something "wrong"...he'll probably forget it in his affair fog.
Wishing you strength!
M 44, H 46 D11, D9, D5 Married 12 years PA confirmed 9/2011 I filed 3/2012 H moved out 7/2012